The `` Downton Abbey '' phenomenon just keeps getting bigger .

Sunday 's season four premiere of the upstairs-downstairs drama on PBS surpassed the comparable ratings for every previous episode . According to Nielsen data , at least 10.2 million viewers tuned in live -LRB- or within a few hours via digital video recorders -RRB- on Sunday night , up from 7.9 million at the start of season three and 8.2 million at the end of it .

This was more than a `` personal best '' for `` Downton . '' The season four premiere outperformed every other drama on Sunday night , too . CBS 's `` The Good Wife , '' for instance , had 9.2 million viewers ; ABC 's `` Revenge '' had 6.7 million . -LRB- All these totals will increase once several days of digital video recorder viewership is factored in . -RRB-

PBS is n't rated like a traditional network because it does n't carry traditional commercials .

But even last season 's `` Downton '' premiere was described as one of the highest-rated events in the history of the public broadcasting network ; analysts said PBS had n't seen numbers this high since the premiere of the `` Civil War '' documentary series in 1990 . An apples-to-apples comparison is impossible because of changes in ratings methodology . But the season four premiere affirms that `` Downton '' is making history for the network .

Season four , of course , debuted several months ago in the United Kingdom . PBS has received no small amount of criticism for its decision to delay the episodes in the United States , and the network 's executives are aware that some fans get a sneak peek by finding the episodes illegally on the Internet . But they say the sky-high ratings two seasons in a row are proof that their scheduling strategy is a wise one .

Paula Kerger , the chief executive of PBS , said in a statement on Monday , `` I 'm so pleased that millions of viewers have returned to ` Downton Abbey ' on their local PBS stations for what has become a post-holiday tradition . ''

Rebecca Eaton , the executive producer of `` Masterpiece , '' added , `` Julian Fellowes has written every word of all four seasons of ` Downton , ' and I toss him a huge bouquet on behalf of his American fans . ''

The premiere ratings suggest `` Downton '' could grow to be even more popular as the season progresses . Last year 8.2 million viewers tuned in on the night of the season three finale , and more than 4 million tuned in later , for a total of 12.3 million . The second-to-last episode of the season did even better once delayed viewership was totaled up : 12.4 million . That 's the next `` personal best '' for the drama to beat .

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At least 10.2 million viewers tune in Sunday to season 4 premiere

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That 's up from 7.9 million at the start of `` Downton 's '' season three

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PBS executive says the show has become a post-holiday tradition